Control means for transmitters



Nov. 7, 1939.

D. E. WATTS CONTROL MEANS FOR TRANSMITTERS Filed June 19, 1957 *lill s tw@ P .E n oa r ,mw m im mmf@ W. Y. .D

My invention relates to radio transmitter apparatus, and particularly to starting and control arrangements for keyed transmitters, wherein starting of the transmitter circuits and keying of the transmitter may be accomplished either at the transmitter or from a remote point.

The general object of the invention is to provide improved and simpliiedlocal and remote starting, control, and keying means for transmitter apparatus supplied from an alternating current source and having a keying circuit supplied frorn a direct current source.

A further object is to provide an improved former MB. indicating meansy operating in conjunction with the local and remote control means, to indicate power conditions in the circuits supplied with alternating current power.

A still further object is to provide an improved means for standby operation of the transmitter apparatus whereby tube elements of the apparatus are maintained in readiness for immediate minal Si of transformer operation of the system either from the local vor the remote control point.

The novel features which I believe to be characteristic of my invention are set forth with particularity in the appended claims. My invenof the latter actuating winding and primaries are tion itself, however, both as to its organization and method of operation together with further objects and advantages thereof may best be understood by reference to the following description taken in connection with the accompanying drawing, in which the single figure illustrates diagrammatically a radio transmitter apparatus in which my invention has been embodied.

In the drawing, the numeral l designates generally a local control station at the transmitter apparatus, and the numeral 2 designates a remote control station. An alternating current source represented by the power lines 3 is adapted to be connected through a main switch i and a relay E, having an actuating winding li and extra contacts l, to the primary of an anode transformer 8 of a rectier 9 for supplying anode curlay 2 i. rent to the various tubes (not shown) of the transmitter. Two lines of the source 3 are conconnected also through extra contacts li of relay nected to the primary of a transformer ifi for supplying current, through a switch and relay means to be presently described to the primary of a transmitter-cathode transformer il, to the primaries of the cathode transformer l2 and the anode transformer i3 of a keying-circuit supply rectifier lli, and to the primary of the cathode transformer l5 of the rectier 9.

For controlling the current from transformer i0 to the foregoing elements, one terminal, I6, of

Patented Nov. 7, 1939 CONTROL MEANS FUR TRANSMITTERS Donald 1E. Watts, Schenectady, N. Y., assignor to General Electric Company, a corporation of New York Application June 19, 1937, Serial No. 149,117

transformer it is connected to two terminals Il and i3 of a local start-stop double-pole switch I9, through the actuating winding 2li of a starting contactor or relay Ei and through a power indicator or signal lamp 22. minals 23 and 2li of the switch it) are connected respectively to terminals 2 and 2t of a localand-remote control triple-pole switch 2l. one of the blades 28 of the latter switch which is adapted to be connected to terminal 23 of switch i9 is connected through contacts 29 of an interlock relay till to the other terminal 3i of transrhe opposite ter- Terminal iii of transformer IE) is further connected through a regulating resistance 32 to one terminal of the primary of transmitter-cathode transformer li, the other terminal of the latter primary being adapted to be connected through contacts tt of relay 2l, contacts Sli of relay it, and contacts 3f of relay 2i to the other ter- Terminal it of transformer lil is connected also to a terminal of the actuating winding t of a time-delay relay 3l and to terminals of the primaries of cathode transformers i2 and it. The opposite terminals adapted to be connected through contacts 3ft of relay 3U and contacts 35 of relay 2l to terminal 3l of transformer it.

Terminal it of transformer i@ is adapted to be connected also through the contacts @iii of timedelay relay (il and contacts 3@ of relay 2l to a terminal of the primary of anode transformer i3 and to a terminal of the actuating coil ii of relay 5. The opposite terminal of the latter primary is adapted to be connected through contacts it of relay 2i, contacts 354i of relay til, and contacts 35 of relay il to terminal 3l of transformer ld, and the opposite terminal of actuating winding ti is adapted to be connected to terminal 3! of transfo-rmer iii through contacts 33 of relay 2l, contacts 3ft of relay 3l] and contacts 35 of re- Terminal it of transformer l@ is adapted to be 5 to one terminal of an anode current indicator or signal lamp M at the local control station i, the opposite terminal of which lamp is adapted to be connected to terminal 3l of transformer it) either through start-stop switch blade Eil of local-remote control switch 2l when this switch is in its local control position as illustrated, and contacts 29 of relay 3U, or through contact 26 and blade t2 of local-remote control switch 2l when this switch is in its lower or re- Ll, contact 25 and That mote-control position, a start-stop switch it at remote control station 2, contact lll and blade E8 of switch 2l, and contacts El@ of relay til. Terminal l5 of transformer l5 is adapted to be connected also through extra contacts l of relay 5 to one terminal of an anode current indicator or signal lamp l5 at the remote-control station The opposite terminal of indicator i5 is adapted to be connected to terminal 3l of transformer l@ through remote start-stop switch contact fill and blade 23 of local-remote control switch 2l when this switch is in its lower or remote-control position, and contacts 2S of relay A keying circuit (not shown) for the trancrnitter apparatus is adapted to be connected in circuit with the terminals "it and @il of the keying-circuit supply rectier ll by a keying means represented by a key @il at the local control station l when local and remote control switch 2l is either in its local or its remote control position, and by a key 9, at the remote control station 2, only when the switch 2l' is in its lower or remote control position. The terminals of local control key #i8 re connected respectively to blades 28 and E@ of local-and-remote control switch 2l and the terminals of remote control key d5 are connected respectively to terminals and 5l of switch 2l. The same wire or lead thus functions as a connection means between the lower terminal fill of switch at the local station l and the start-stop switch i3 and key at the remote control station a total of four wires only being required to connect the start-top means, the keying means and the anode current indicator at remote control station il of the local control station i.

To enable the cathodes of the system to be energized without energization of the anode circuits and anode current indicators until desired, a stand-by switch is connected across the contacts 35 of starting contactor or relay 2i.

To energize the interlock relay 3c co' tinuously during operation of the system, the teof its actuating winding 553 are connected respectively to the terminals E6 and 3i of transformer ill. Emergency stop means, represented by an emergency stop switch are included in one or both of the leads, as lead 5S, connecting actuating coil 5d, of interlock relay to transformer lll.

In operation, assuming it is desired to control the system from local station i, main switch Il being closed and stand-by switch open and the actuating winding 54S of interlock rei being energized by current from transformer l to close contacts 29 and Sd, the loca- "ld-remote control switch 2l is placed in its upper, or local control, position and local start-stop switch i@ is closed. Power indicator lamp actuating coil 20 of starting contacter 2i, are thereupon energized by current from transformer iii through the circuit extending from terminal of transformer ifi, through coil Ztl and lamp parallel, lower contacts of switch i9, contact and 28 of switch contacts Eil of relay St, back to terminal 3l of transformer lil. Upon energizing of actuating coil fill as above described, contacts 39, il@ and of relay 2l are closed. The following elements are then also energized from transformer lll: transmitter-cathote transformer l l is energized through the circuit extending from terminal lli of transformer il?, through. resietance 32, the primary of transformer il, contacts 33 of contacter 2l, contacts of .relay contacts 35 of contactor 2l, back to terminal Si of transformer Il); keying-circuit-rectier cathode transformer l2 is energized through the circuit extending from terminal i6 of transformer lil, through the primary of transformer i2, contacts 34 of relay Sii, contacts 35 of contacter 2l, back to terminal 3l of transformer lli; transmitteranode-rectifier cathode transformer l5 is energized through the circuit extending from terminal l5 of transformer l, through the primary of transformer i5, contacts 35i of relay 3l), contacts 35 of contacter 2l, back to terminal 3l of transformer ill; and actuating coil 35 of time-delay relay 3l is energized through the circuit extending from terminal i6 of transformer i9 through coil B, contacts 34 of relay 3 contacts 35 of contactor 2l, back to terminal 3l of transformer EG.

After a predetermined interval, for example thirty seconds, the contacts 38 of time-delay relay 3l close, thereby causing keying-circuit rectifieranode transformer i3 to be energized through the circuit extending from terminal i6 of transformer l, through contacts 38 of relay 3l, contacts of contactor 2l, the primary of transformer i3, contacts lli of contactor 2l, contacts til of relay 39, contacts 35 of contactcr 2i, back to terminal 3l of transformer it, and also causing actuating coil f5 of relay 5 to be energized from transformer l d through the circuit extending 'from terminal l5 of transformer lil, through contacts of relay 3l, contacts 3S of contactor 2i, coil contacts 33 of contacter 25, contacts 343 of relay 3l, contacts 35 of contactor 2l, and back to terminal 3l cf transformer lil. The contacts of relay 5 thereupon close causing transmitter-anode transformer 8 to be energized from lines 3 directly, and anode current indicator il to be energized from transformer l El through the circuit extending from terminal i6 of transformer it, contacts l of switch 5, indicator lll, switch i9, contact 25 and blade 2&3 of switch 2l, contacts 29 of relay 353, back to ter` minal 3l of transformer l).

rlhe transmitter keying circuit is now ready to be energized from keying-circuit rectifier lli and the transmitter may be keyed by key i8 at the local station I. At the same time connection of the remote control station 2 to the startin indicating, and keying circuits of the system is cut off at the local-and-remote control switch 2l.

Assuming now that it is desired to start and to key the system from remote station 2, main switch l and local start-stop switch SQ 1ceing in closed position as before, the local-and-remote control switch 2l is placed in its lower or remote control position and remote start-stop switch [33 is closed. Actuating winding 2t of starting conf tactor Zi is thereupon energized from transformer lli through the circuit extending from terminal it of transformer lll through winding Ell, the upper contacts i8 and 2li of switch contact ,'li and blade 42 of switch E", remote control switch 43, contact lil and blade 28 of switch 2l, contacts 25 of interlock relay 39, back to terminal 3l of transformer lll. Transformers ll, i2 and l5 actuating coil 35 of time-delay 3'! are thereupon energized, followed by the closing of the timedelay relay contacts 38 and the consequent energizing of transformer E3, actuating coil 6 of relay 5, transformer 3, and anode current indicator 22, as above explained in connection with operation from the local station. Remote anode-current indicator or lamp l5 is also energized, by currentI from transformer l@ through the circuit extending from terminal i6 of transformer i3 through contacts l of relay 5, lamp 15.5, switch 133, Contact lifl and blade 28 of switch 2l, contacts 29 of relay 35i, back to terminal 3l of transformer lli. The system may now be keyed either from the local station l by key it or from the remote station t by key dil. In the latter case the keying current from rectifier lll iiows from the rectiner, through the keying circuit of the transmitter, blade titl and contact 5l of switch il, to the remote stan tion key thence through line 52, contact ,fit1 and blade 28 of switch 2l, and back to the rectifier.

To place the system in stand-by condition, wherein only the cathodes of the rectiners El and lll, and the actuating coil til of interlock relay tu, are maintained in energized condition, main switch il being closed and interlock relay t@ being held in closed position by current from transformer it, local start-stop switch i9 is assumed to be open if localmand-remote control switch 2l is in its upper or local control position and remote start-stop switch l2-l is assumed to be open if switch 2f is in its lower or remote control position. Standby switch 5t is closed thereby causing transformer l@ to energize cathode transformers i2 and it of rectiiiers lfl and il respectively, 'through a circuit extending from the terminal iii of transformer ill, through the primary windings of transformers lll and in parallel, contacts 31E of relay switch 53, and back to terminal 3l of transformer lll.

Closing of standby switch E53 also causes trans former lil to energize actuating winding t6 of time-delay relay .itl through the circuit extending from terminal iii of transformer lil, through winding tt, contacts of relay tu, switch llt, back to terminal tl of transformer ill, the contacts 33 of relay 3l closing after the predetermined time interval. Anode current is not, however, supplied to transformers lil and ii, since contacts 35 of relay 2i, connected to transformer i3 and to the actuating winding of relay t, remain open. by means either of the local switch i9 or of the remote switch t3, switch 2l being in the appropriate position for local or for remote operation, anode voltage is immediately applied to the key- .ingurrent rectifier lil through transformer i3 which is energized from transformer it through the circuit extending from terminal lll of transformer lil, through contacts til of time-delay relay 3I, contacts 39 of contactor ti, the primary of transformer lil, contacts it of contacter 2l, contacts 34 of relay 3U, contacts 35 of contacter 2l, back to terminal 3l of transformer it. At the same time actuating winding t of switch 5 is energized from transformer it through the circuit extending from terminal it of transformer it, through contacts t3 of relay tl, contacts 39 of contacter 2l, winding t, contacts 33 of contactor 2l, contacts Bt of relay til, contacts itil of contactor 2l, back to terminal 3l of transformer lil. Switch 5 thereupon closes and anode voltage is supplied to rectier li through transformer rectifier il then applying anode voltage to the transmitter anodes. Further, the transmitter cathodes also are energized from transformer il, which is energized from transformer lil through the circuit extending from terminal it of transformer lil, through resistance 32, the primary of transformer Il, contacts of contactor 2|, contacts td of relay 3E), contacts 35 of contactor fl, back to terminal 3l of transformer Ill. The system is then ready for keying as hereinabove described.

If it is found desirable, from the standpoint of tube operation to energize the transmitter cathodes continuously when the controls are in the If now the transmitter is started i standby position, it is possible to accomplish this by connecting a link across contacts 33 of relay 2l.

In case the emergency stop means represented by stop switch 55 is operated, actuating coil 54 ,l

of interlock relay til is de-energzed. By the opening of contacts trl of relay 3E), all of the cathode transformers il, l2 and I5 are disconnected from supply transformer it. By the opening of the other contacts 25J of relay 3@ the actuating winding at of starting relay 2l is also deenergized, thus insuring the opening of the con- 'ta-cts of the latter relay, and complete stoppage of the system, when the interlock relay 30 is de-energized.

My invention has been described herein in a particular embodiment for purposes of illustration. It is to be understood, however, that the invention is susceptible of various changes and modications and that by the appended claims I intend to cause any such modifications as fall within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States, is:

i. In a transmitter apparatus comprising a cathode heating circuit, an anode supply circuit, and a keying circuit, means to control said apparatus from a local station at said apparatus and subsequently from a remote station, said means including a local and remote switch at said local station, means operative when said switch is in its local position to energize said cathode circuit, to energize said anode circuit after a predetermined time interval, to operate said keying circuit from said local station only, and to prevent control of said circuits from said remote station, and means operative when said switch is in its remote position to energize said cathode and anode circuits and to operate said keying circuit from said remote station.

2. In a transmitter apparatus comprising a local and a remote control station, a cathode heating circuit and an indicator therefor at said local station, an anode supply circuit and indicators therefor at both said stations, and a keying circuit, a local and remote control switch at said local station, means operative when said switch is in local position to energize said cathode heating circuit and said indicator therefor, to energize said anode circuit and the local station indicator therefor after a predetermined time interval, to operate said keying circuit from said local station only, and to prevent control of said circuits and said anode circuit indicators from' said remote statiomand means operative when said switch is in its remote position to operate said keying circuit and to energize said cathode circuit, said anode circuit, and the remote station indicator therefor from said remote station.

3. In combination, in a transmitter apparatus, a current source, a cathode heating circuit, an anode supply circuit, a time-delay relay adapted to connect said source to said anode circuit, a key ing circuit, a local and remote control switch, a normally open standby switch, means operative upon closing of said standby switch to disconnect said cathode heating circuit and said anode supply circuit lfrom said source, means operative when said first-named switch is moved to its local position while said standby switch remains closed to connect said anode circuit to said source through said relay, to operate said keying circuit only from a point at said apparatus, and to prevent control of said apparatus from a remote 5 and to operate said keying circuit from said remote point.

4.1m a transmitter apparatus comprising a cathode heating circuit, an anode supply circuit, and a keying circuit, means to control said apv1() paratus from a local station at said apparatus and subsequently from a remote station, said means including a local and remote switch at said local station, means operative when said switch is in its local position to energize said cathode and anode circuits, to operate said keying circuitJ from said local station only, and to prevent control of said circuits from said remote station, means including at said remote station a start-stop switch only to lenergize said cathode and anode circuits through said local and remote switch when lastlnamed switch is in its remote position, and means including at said remote station keying contacts only to operate said keying circuit through said local and remote switch when said last-named switch is in its remote position.

5. In a transmitter apparatus comprising a local and a remote control station, a cathode heating circuit and an indicator therefor at said local station, an anode supply circuit and indicators therefor at both stations, and a keying circuit, a local and remote control switch at said local station, means operative when said switch is in its local position. to energize said cathode circuit and said indicator therefor, to energize said anode circuit and the local station indicator therefor, to operate said keying circuit from said local station only, and to prevent control of said circuits and said anode circuit indicators from said remote station, means including at said remote station a start-stop switch only to energize through said local and remote switch said cathode and anode circuits and said remote station indicator for said anode circuit when said lastnamed switch is in its remote position, and means including at said remote station keying contacts only to operate said keying circuit through said local and remote switch when said last-narned switch is in its remote position.

6. In combination, in a transmitter apparatus, a current source, a cathode heating circuit, an anode supply circuit, a time delay relay adapted to connect said source to said anode circuit, a keying circuit, a local and remote control switch, a standby switch', means operative when said rstnamed switch is moved to its local position while said standby switch remains closed to connect said anode circuit to said source through said relay, to operate said keying circuit from a point at said apparatus only, and to prevent control of said apparatus from a remote point, means including at said remote point a start-stop switch only to connect said anode circuit to said source through said relay and said local and remotey switch when said last-named switch is moved to its remote position, and means including at said remote point keyinnr contacts only to operate said keying circuit through said local and remote switch when said last-named switch is moved to its remote position.

DONALD E. WATTS. 

